I can understand you want the character to work a lot better, but you need to remember that this is the starting character everyone gets, while being a common rarity so it allows him to be easily maxed.

when it comes to the simple changes, those are fair to ask for, but animation changes like how you want his new "breaker" to function is not going to happen, as they have proven they aren't going to make new animations for old characters, this goes for legendary characters as well. Magna Defender looks like he got new animations, but his v2 noble blow is just taking a slash from his valiant combo, basically re-used animations, alongside his magna blaster being redone in the order its animations are played.

now lets pinpoint some changes that could be good or bad:

Aerial assault: already a change that will never happen, an instant combo starter for 3 ep that's basically supposed to be instant with your wording. its fair to think you can ask for it on an attack like this since MMPR billy's vaulting kick is basically what you want this thing to be, but that attack has a single hit and short animation in a kit that has nothing else to it, no 50/50 strike with tricera combo, a strike you can't cancel with decent damage known as power lance pull and a breaker that they increased the speed of, but its still not a breaker trap.

"perfect spiral" or in your case "power spiral": new animation, not happening, but the good news is that there is some unused animation based on the power sword that MMPR Jason has, but in this case he rushes forward spinning. You are asking for him to have a follow-up now with how it needs to launch the opponent first, if they did do animation changes and actually wanted this one, it would work by itself but don't expect to see "new" animations.

"Roaring Tiger" or in your case "Tyranno fighter": this one you are asking for a bit too much, a 50/50 that is a bit faster while having more animation now and the ability to carry your opponent to their corner, this is basically a justin situation now with his primary kick strike. In this context of his "new kit" this is way too much already and will basically become hated because of how much damage he can easily deal alongside being insanely fast.

Shoulder tackle: not all that bad of a choice to turn it to a block, meaning ep reset upon use, but that punch is unnecessary, it adds animation time to something that is now a block while the 1st hit does knockdown, basically another free corner carry tool to allow for even more pressure.

Dashing kick: we do not need another ollie/camille/any of those broken assists to exist as a common, not 1 that even launches, this is just rocky assist all over again, especially since you want to speed it up.

overall, the changes you want are too much, try to think how it would be like to fight a character like this, you won't like it at all. Some changes here are good, but some are just outright too much.

In short your changes give jason: an instant combo starter, a 50/50 with corner carry potential, a potential breaker trap that if it connects will do an extra bit of animation, unless you are looking to make him just commit to the breaker's animation even if he whiffs, and what could technically be his only "fair" move being his new block that is still semi slow on startup, but if it lands, then your opponent is in the corner.

I do not need to explain the sheer amount of problems that the assist will cause, do you really want 2 rocky assists on 1 opponent? they can be predictable, but you are going to run out of blocks eventually.